Adding new rule for enforcing new lines at the end of file, fixes #89

README.md

@@ -87,6 +87,7 @@ playground for learning and exploring.
 * **[MD043](doc/Rules.md#md043)** *required-headings/required-headers* - Required heading structure
 * **[MD044](doc/Rules.md#md044)** *proper-names* - Proper names should have the correct capitalization
 * **[MD045](doc/Rules.md#md045)** *no-alt-text* - Images should have alternate text (alt text)
+* **[MD046](doc/Rules.md#md046)** *new-line-eof* - New lines at the end of file
 
 See [Rules.md](doc/Rules.md) for more details.
 
@@ -101,7 +102,7 @@ Tags group related rules and can be used to enable/disable multiple rules at onc
 * **accessibility** - MD045
 * **atx** - MD018, MD019
 * **atx_closed** - MD020, MD021
-* **blank_lines** - MD012, MD022, MD031, MD032
+* **blank_lines** - MD012, MD022, MD031, MD032, MD046
 * **blockquote** - MD027, MD028
 * **bullet** - MD004, MD005, MD006, MD007, MD032
 * **code** - MD014, MD031, MD038, MD040

doc/Rules.md

@@ -1544,3 +1544,30 @@ Or with reference syntax as:
 Guidance for writing alternate text is available from the [W3C](https://www.w3.org/WAI/alt/),
 [Wikipedia](https://en.wikipedia.org/wiki/Alt_attribute), and
 [other locations](https://www.phase2technology.com/blog/no-more-excuses-definitive-guide-alt-text-field).
+
+<a name="md045"></a>
+
+## MD046 - New lines at the end of file
+
+Tags: blank_lines
+
+Aliases: new-line-eof
+
+This rule is triggered when there is no new line at the end of the file.
+
+Example that triggers the rule:
+
+```markdown
+# File ending without new line
+
+This file ends without new line.
+```
+
+To fix the violation, add new line at the end of the file:
+
+```markdown
+# File ending with new line
+
+This file ends with new line.
+
+```

lib/md046.js

@@ -0,0 +1,22 @@
+// @ts-check
+
+"use strict";
+
+const shared = require("./shared");
+const { isBlankLine } = shared;
+
+module.exports = {
+  "names": [ "MD046", "new-line-eof" ],
+  "description": "New lines at the end of file",
+  "tags": [ "blank_lines" ],
+  "function": function rule(params, onError) {
+    const lastLineNumber = params.lines.length;
+    const lastLine = params.lines[lastLineNumber - 1];
+    if (!isBlankLine(lastLine)) {
+      onError({
+        "lineNumber": lastLineNumber,
+        "detail": "file does not end with new line"
+      });
+    }
+  }
+};

lib/rules.js

@@ -48,7 +48,8 @@ const rules = [
   require("./md042"),
   require("./md043"),
   require("./md044"),
-  require("./md045")
+  require("./md045"),
+  require("./md046")
 ];
 rules.forEach((rule) => {
   const name = rule.names[0].toLowerCase();

schema/markdownlint-config-schema.json

@@ -1255,6 +1255,16 @@
       "type": "boolean",
       "default": true
     },
+    "MD046": {
+      "description": "MD046/new-line-eof - New lines at the end of file",
+      "type": "boolean",
+      "default": true
+    },
+    "new-line-eof": {
+      "description": "MD046/new-line-eof - New lines at the end of file",
+      "type": "boolean",
+      "default": true
+    },
     "headings": {
       "description": "headings - MD001, MD002, MD003, MD018, MD019, MD020, MD021, MD022, MD023, MD024, MD025, MD026, MD036, MD041, MD043",
       "type": "boolean",

test/fenced_code_without_blank_lines.md

@@ -39,4 +39,4 @@ text
 
 ```
 code at end of file without newline
-```
+``` {MD046}

test/lists_without_blank_lines.md

@@ -72,4 +72,4 @@ code
 
 text
 
-* list (on last line without newline)
+* list (on last line without newline) {MD046}

test/markdownlint-test.js

@@ -248,7 +248,7 @@ module.exports.resultFormattingV1 = function resultFormattingV1(test) {
   const options = {
     "strings": {
       "truncate":
-        "#  Multiple spaces inside hashes on closed atx style heading  #"
+        "#  Multiple spaces inside hashes on closed atx style heading  #\n"
     },
     "files": [
       "./test/atx_heading_spacing.md",
@@ -350,7 +350,7 @@ module.exports.resultFormattingV2 = function resultFormattingV2(test) {
   const options = {
     "strings": {
       "truncate":
-        "#  Multiple spaces inside hashes on closed atx style heading  #"
+        "#  Multiple spaces inside hashes on closed atx style heading  #\n"
     },
     "files": [
       "./test/atx_heading_spacing.md",
@@ -446,14 +446,14 @@ module.exports.stringInputLineEndings = function stringInputLineEndings(test) {
   test.expect(2);
   const options = {
     "strings": {
-      "cr": "One\rTwo\r#Three",
+      "cr": "One\rTwo\r#Three\n",
-      "lf": "One\nTwo\n#Three",
+      "lf": "One\nTwo\n#Three\n",
-      "crlf": "One\r\nTwo\r\n#Three",
+      "crlf": "One\r\nTwo\r\n#Three\n",
-      "mixed": "One\rTwo\n#Three",
+      "mixed": "One\rTwo\n#Three\n",
-      "crnel": "One\r\u0085Two\r\u0085#Three",
+      "crnel": "One\r\u0085Two\r\u0085#Three\n",
-      "snl": "One\u2424Two\u2424#Three",
+      "snl": "One\u2424Two\u2424#Three\n",
-      "lsep": "One\u2028Two\u2028#Three",
+      "lsep": "One\u2028Two\u2028#Three\n",
-      "nel": "One\u0085Two\u0085#Three"
+      "nel": "One\u0085Two\u0085#Three\n"
     },
     "config": defaultConfig,
     "resultVersion": 0
@@ -913,7 +913,7 @@ module.exports.noInlineConfig = function noInlineConfig(test) {
         "",
         "<!-- markdownlint-enable-->",
         "",
-        "\tTab"
+        "\tTab\n"
       ].join("\n")
     },
     "noInlineConfig": true,
@@ -1089,7 +1089,7 @@ module.exports.missingStringValue = function missingStringValue(test) {
 };
 
 module.exports.readme = function readme(test) {
-  test.expect(109);
+  test.expect(111);
   const tagToRules = {};
   rules.forEach(function forRule(rule) {
     rule.tags.forEach(function forTag(tag) {
@@ -1155,7 +1155,7 @@ module.exports.readme = function readme(test) {
 };
 
 module.exports.doc = function doc(test) {
-  test.expect(312);
+  test.expect(319);
   fs.readFile("doc/Rules.md", shared.utf8Encoding,
     function readFile(err, contents) {
       test.ifError(err);
@@ -1883,7 +1883,7 @@ module.exports.configBadHybridSync = function configBadHybridSync(test) {
 
 module.exports.allBuiltInRulesHaveValidUrl =
   function allBuiltInRulesHaveValidUrl(test) {
-    test.expect(123);
+    test.expect(126);
     rules.forEach(function forRule(rule) {
       test.ok(rule.information);
       test.ok(Object.getPrototypeOf(rule.information) === URL.prototype);
@@ -2240,7 +2240,7 @@ module.exports.customRulesNpmPackage = function customRulesNpmPackage(test) {
   const options = {
     "customRules": [ require("./rules/npm") ],
     "strings": {
-      "string": "# Text\n\n---\n\nText"
+      "string": "# Text\n\n---\n\nText\n"
     },
     "resultVersion": 0
   };
@@ -2539,7 +2539,7 @@ module.exports.customRulesOnErrorLazy = function customRulesOnErrorLazy(test) {
       }
     ],
     "strings": {
-      "string": "# Heading"
+      "string": "# Heading\n"
     }
   };
   markdownlint(options, function callback(err, actualResult) {
@@ -2626,7 +2626,7 @@ module.exports.markdownItPluginsSingle =
     test.expect(2);
     markdownlint({
       "strings": {
-        "string": "# Heading\n\nText [ link ](https://example.com)"
+        "string": "# Heading\n\nText [ link ](https://example.com)\n"
       },
       "markdownItPlugins": [
         [
@@ -2651,7 +2651,7 @@ module.exports.markdownItPluginsMultiple =
     test.expect(4);
     markdownlint({
       "strings": {
-        "string": "# Heading\n\nText H~2~0 text 29^th^ text"
+        "string": "# Heading\n\nText H~2~0 text 29^th^ text\n"
       },
       "markdownItPlugins": [
         [ pluginSub ],
@@ -2704,7 +2704,7 @@ $$
 1
 $$$$
 2
-$$`
+$$\n`
       },
       "markdownItPlugins": [ [ pluginKatex ] ],
       "resultVersion": 0
@@ -2719,3 +2719,25 @@ $$`
       test.done();
     });
   };
+
+module.exports.newLineAtTheEndOfFile =
+  function newLineAtTheEndOfFile(test) {
+    test.expect(2);
+    markdownlint({
+      "files": "./test/new_line_EOF.md"
+    }, function callback(err, actual) {
+      test.ifError(err);
+      const expected = { "./test/new_line_EOF.md":
+      [
+        { "lineNumber": 3,
+          "ruleNames": [ "MD046", "new-line-eof" ],
+          "ruleDescription": "New lines at the end of file",
+          "ruleInformation": `${homepage}/blob/v${version}/doc/Rules.md#md046`,
+          "errorDetail": "file does not end with new line",
+          "errorContext": null,
+          "errorRange": null }
+      ] };
+      test.deepEqual(actual, expected, "Unexpected issues.");
+      test.done();
+    });
+  };

test/new_line_EOF.json

@@ -0,0 +1,4 @@
+{
+  "default": true,
+  "MD046": false
+}

test/new_line_EOF.md

@@ -0,0 +1,3 @@
+# File ending without new line
+
+This file ends without new line.

test/required-headings-missing-last.md

@@ -4,4 +4,4 @@ One
 Two
 ---
 
-{MD043}
+{MD043} {MD046}